Domain Name System (DNS) server, in general, refers to a service or a server that translates a domain name, such as, a website name or a Uniform Resource Locator (URL) into an Internet Protocol (IP) address. The IP address may be an identifier of a node (computing device), in particular, a host, within a network of nodes and may be utilized for communication between the host and other nodes within the network. The host, as identified by the IP address, may store content associated with the website name or the URL and may provide the content to the DNS server and/or a client device of a user that requested the domain name. For translating the domain name into the IP address, the DNS server may utilize mapping information that generally includes records of most frequently requested domain names with their respective IP addresses.
On some instances, the DNS server may not be able to translate the domain name to the corresponding IP address, due to reasons, such as unavailability of the mapping information for the domain name. The DNS server, on such occasions, may request another DNS server, often referred to as a backend server or an authoritative server, to provide the corresponding IP address. The backend server, upon receiving the request, may search for the corresponding IP address within mapping information stored in the cache (or database) of the backend server and provide the corresponding IP address to the DNS server. A host may then be identified based on the IP address for retrieving content associated with the domain name and providing the content to the client device.
It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.